Liquid crystal device and electronic apparatus

ABSTRACT

Ambient light incident upon a polarizer  105  passes through a liquid crystal layer  103  and is then reflected by reflective films  116  via transparent electrodes  115 . The reflected light passes again through the liquid crystal layer  103  and the polarizer  105  and is output to the outside thereby displaying an image in a reflective displaying mode. The reflective films  116  are disposed at locations corresponding to the respective transparent electrodes  115  such that they are spaced from each other. In this structure, some ambient light passes through the spaces between adjacent transparent electrodes  115 , however, such light is not reflected by the reflective films  116  toward the outside and thus a reduction in contrast due to such reflection is prevented.

This Application is a 371 of PCT/JP99/01864 filed Apr. 7, 1999

TECHNICAL FIELD

The present invention relates to the field of liquid crystal devices,and more particularly to the structure of liquid crystal devices ofreflective type and of transflective type, and also to an electronicapparatus using such a liquid crystal device.

BACKGROUND ART

Various types of liquid crystal devices are known in the art. Theyinclude a reflective liquid crystal device which displays an image byreflecting ambient light through a liquid crystal by reflecting meansprovided in the device, a transmissive type liquid crystal device inwhich light emitted from a light source provided in the device is passedthrough a liquid crystal and output to the outside thereby forming animage, and a transflective liquid crystal device capable of switchingits displaying mode between reflective and transmissive modes.

Of these liquid crystal devices, reflective liquid crystal devices canoperate with very low power consumption because they need no lightsource. Because of such an advantage, the reflective liquid crystaldevice is widely used as a display unit in portable devices and othervarious systems.

In the transflective liquid crystal device, an image is displayed in thetransmissive mode using a light source when used in a dark environment.However, when used in a light environment, an image is displayed usingambient light as in the reflective liquid crystal device, and thus itneeds low power consumption. Because of such an advantage, thetransflective liquid crystal device is widely used as a display unit inportable devices and other various systems. A typical transflectiveliquid crystal device is, as disclosed in, for example, Japanese UtilityModel Publication No. 57-049271, composed of a polarizer, atransflector, and a backlight which are successively disposed on theouter surface, opposite to the viewing side, of a liquid crystal panel.A transflective liquid crystal device with improved brightness isdisclosed in Japanese Unexamined Patent Publication No. 8-292413. Inthis liquid crystal device, a transflector, a polarizer, and a backlightare successively disposed on the outer surface, opposite to the viewingside, of a liquid crystal panel. Because there is no polarizer betweenthe liquid crystal cell and the transflector, an image with improvedbrightness can be displayed.

With recent advances in portable devices and office automation devices,there is an increasing need for color liquid crystal devices. In manycases, the capability of displaying a color image is also required insystems or devices using a reflective or transflective liquid crystaldevice. To realize a liquid crystal device having the capability ofdisplaying a color image in the reflective or transflective mode, acolor filter having a large number of colored areas of R (red), G(green), and B (blue) is disposed on one of a pair of substrates betweenwhich a liquid crystal is disposed. To avoid mixing among differentcolored areas of the color filter, and to avoid a reduction in thecontrast ratio due to light-struck (white defects) caused by the spacesbetween adjacent colored areas, a light shielding film generally calleda black mask or a black matrix is disposed in the spaces betweenadjacent colored areas.

However, an essential problem of the reflective liquid crystal devicedescribed above is that because an image is displayed using ambientlight, it is difficult or impossible to see the image in a darkenvironment. To obtain better viewability, it is important to increasethe reflectance to ambient light incident on the liquid crystal device,and also to increase the ratio of light which is reflected and outputfrom the liquid crystal device to the outside as display light whichmakes contribution to display contrast relative to the total ambientlight input to the device. However, in the reflective liquid crystaldevice described above, the reflectance and the ratio of output light toinput light are not sufficiently high. In the case of the reflectiveliquid crystal device in which a transparent substrate is disposedbetween the liquid crystal layer and the reflector, the problem is thatdouble images or dull images occur in an image displayed. If a colorfilter is combined with this liquid crystal device, parallax makes itdifficult to obtain desired colors. When the liquid crystal deviceincludes a color filter, if a structure including no black matrix isemployed to avoid absorption of light by the black matrix therebyincreasing the image brightness, then light passing through spacesbetween adjacent colored areas is reflected by the reflector. Thiscauses a greater part of ambient light to be output from the liquidcrystal device without making any contribution to the image contrast orformation of an image, and thus causes a reduction in the contrastratio. Japanese Unexamined Patent Publication No. 9-258219 discloses areflective color liquid crystal device in which a reflector is disposedin contact with a liquid crystal layer. Also in this liquid crystaldevice, if spaces between adjacent colored areas of the color filter arenot covered with a black mask so as to increase the image brightness asdescribed above, some ambient light, which passes through the spaceslocated between adjacent colored areas and covered with no black mask,is reflected by the reflector and output in mixture with imaging lightto the outside of the liquid crystal device. This results in mixingcolors, and it makes the colors dull or faded. Further, a contrast ratiois reduced.

As described above, the problem of the conventional reflective liquidcrystal device has difficulty of displaying an image with a highbrightness and a high contrast.

The transflective liquid crystal device disclosed in Japanese UnexaminedPatent Publication No. 8-292413 cited above also has similar problemsassociated with double images and dull images because a transparentsubstrate is disposed between a liquid crystal layer and a transflector.Also in this case, if a color filter is combined with this liquidcrystal device, parallax makes it difficult to obtain desired colors.Japanese Unexamined Patent Publication No. 7-318929 discloses atransflective liquid crystal device in which pixel electrodes which alsoserve as transflective films are formed on the inner surface of a liquidcrystal cell. This patent cited herein also discloses a structure inwhich pixel electrodes formed of ITO (indium tin oxide) are laminated ona transflective film formed of a metal film via an insulating film.However, in this liquid crystal device, it is required to form a largenumber of very small defects such as hole defects or recessed defects orvery small openings in the pixel electrodes which also serve as thetransflective films or in the transflective films on which the pixelelectrodes are formed. This results in an increase in the complexity ofthe device. Furthermore, a special process is additionally required toproduce the openings. This makes it difficult to produce the pixelelectrodes or transflective films with high reliability. In particular,when the pixel electrodes are formed such that they also serve as thetransflective films, it is required that, in the transmissive displayingmode, portions of the liquid crystal, through which light emitted from alight source passes after passing through openings, be driven by obliqueelectric fields generated by pixel electrodes located in non-openingareas. As a result, degradation in image quality occurs due tovariations in orientation of the liquid crystal compared with the casewhere the liquid crystal is driven by vertical electric fields.

On the other hand, in the case where the pixel electrodes are formed viaan insulating film on the respective transflective films formed ofmetal, adjacent pixel electrodes are capacitively coupled with eachother via capacitors formed of the respective pixel electrode, theinsulating films, and the transflective films, and further via thetransflective films. As a result, signals such as image signals suppliedto the plurality of pixel electrodes are mixed with one another or havecross-talk with one another. Hence, the signals have distortion in thewaveforms, which results in degradation in quality of the imagedisplayed. In particular, when the pixel electrodes are also used as thedata lines or segment electrodes via which image signals havingcomplicated waveforms and having a high driving frequency compared withthe scanning electrodes are supplied, the degradation in quality becomesmore serious.

As described above, the conventional transflective liquid crystal devicehas the problem that it is difficult to display a high-brightness andhigh-contrast image.

SUMMARY OF THE INVENTION

In view of the above, an object of the present invention is to provide areflective or transflective liquid crystal device capable of displayinga high-brightness and high-contrast image without producing doubleimages or dull images due to parallax, and also an electronic apparatususing such a liquid crystal device.

A first liquid crystal device according to the present invention canachieve the above object. The first liquid crystal device comprises: apair of first and second substrates; a liquid crystal layer disposedbetween the first and second substrates; a plurality of transparentelectrodes which are formed on a surface, on the side of the liquidcrystal layer, of the second substrate such that the plurality oftransparent electrodes are spaced from each other in a horizontaldirection when seen in a direction perpendicular to the secondsubstrate; and reflective films formed between the plurality oftransparent electrodes and the second substrate, in areas opposing therespective plurality of transparent electrodes, wherein the reflectivefilms are not formed in an area opposing at least some part of a spacebetween the plurality of transparent electrodes.

In this first liquid crystal device according to the present invention,some part of ambient light input from the side of the first substratepasses through the transparent electrodes and such a part of ambientlight is reflected toward the liquid crystal layer by the reflectivefilms formed in the areas opposing the transparent electrodes, therebyforming an image in a reflective displaying mode. In this first liquidcrystal device, because the reflective films are disposed on thesurface, on the side of the liquid crystal layer, of the secondsubstrate, there is substantially no space between the reflective filmsand the liquid crystal layer, and thus double images or dull images areprevented, which would otherwise occur due to parallax. On the otherhand, some part of ambient light input from the side of the firstsubstrate passes through spaces between adjacent transparent electrodes.If such a part of light is reflected toward the liquid crystal layer, adefect known as a bright defect (white defect) occurs, which results ina reduction in the contrast. However, in the first liquid crystal deviceaccording to the present invention, the part of ambient light whichpasses through the spaces between adjacent electrodes after enteringfrom the side of the first substrate further passes through areas wherethere is no reflective film opposing the above-described spaces, andthus such light is never reflected by the reflective films toward theliquid crystal layer. Therefore, it is possible to suppress degradationin image quality due to mixing of imaging light which is reflected bythe reflective films and output to the outside with light which passesthrough the spaces between adjacent transparent electrodes.

In one mode of the first liquid crystal device according to the presentinvention, the reflective films comprise a plurality of reflective filmsspaced from each other in correspondence with the plurality oftransparent electrodes.

In this mode, the part of ambient light which passes through theplurality of transparent electrodes is reflected by the plurality ofreflective films spaced from each other in correspondence with theplurality of transparent electrodes, whereas the part of ambient lightwhich passes through the spaces between adjacent transparent electrodesis not reflected.

In another mode of the first liquid crystal device according to thepresent invention, the first liquid crystal device further comprises acolor filter formed on at least one of the first and second substrates,the color filter including colored areas corresponding to the pluralityof transparent electrodes, wherein the color filter includes no lightshielding area in an area opposing at least some part of a space betweenthe plurality of transparent electrodes.

In this mode, the part of light, which passes through the transparentelectrodes via the colored areas of the color filter, is reflected bythe reflective films thereby displaying a color image in a reflectivedisplaying mode. Herein, the color filter includes no light shieldingarea at least in those areas which oppose the spaces between theplurality of transparent electrodes and in which there is no reflectivefilm. Therefore, ambient light can pass through the spaces betweenadjacent colored areas, which are not covered with light shieldingareas. However, in those areas, there is no reflective film, whichreflects such light. Therefore, mixing of colors between adjacentcolored areas is prevented, which would otherwise occur owing toreflection by the reflective films. Thus, a color image is preventedfrom having dull images or blurring due to mixing of colors.

In still another mode of the first liquid crystal device according tothe present invention, an insulating film is disposed between eachtransparent electrode and each reflective film.

In this mode, because the insulating film is disposed between eachtransparent electrode and each corresponding reflective film, thereflective films are allowed to be formed of a conductive material suchas Al without causing electrical leakage or short circuits among theplurality of transparent electrodes via the reflective films. This alsoallows the pattern, in the horizontal plane, of the reflective films tobe designed in a more flexible fashion.

Alternatively, the transparent electrodes may be formed directly on thereflective films. In this case, the transparent electrodes areelectrically connected to the corresponding reflective films. Therefore,if the reflective films are formed of a conductive material such as Al,the stripe-shaped or island-shaped reflective films serve as redundantstructures for the corresponding transparent electrodes. As a result,the electrode resistance or the interconnection resistance associatedwith the transparent electrodes can be reduced.

The above-described object can also be achieved by a second liquidcrystal device according to the present invention. The second liquidcrystal device comprises: a pair of first and second substrates; aliquid crystal layer disposed between the first and second substrates; aplurality of transparent electrodes formed on a surface, on the side ofthe liquid crystal layer, of the second substrate; a plurality ofconductive reflective films which are formed between the plurality oftransparent electrodes and the second substrate in correspondence withthe respective plurality of transparent electrodes, the plurality ofreflective films being electrically isolated from each other; and aninsulating film disposed between each of the plurality of transparentelectrodes and each of the plurality of reflective films.

In this second liquid crystal device according to the present invention,some part of ambient light input from the side of the first substratepasses through the transparent electrodes and such a part of light isreflected toward the liquid crystal layer by the reflective films formedin the areas opposing the transparent electrodes, thereby forming animage in a reflective displaying mode. In this first liquid crystaldevice, because the reflective films are disposed on the surface, on theside of the liquid crystal layer, of the second substrate, there issubstantially no space between the reflective films and the liquidcrystal layer, and thus double images or dull images are prevented,which would otherwise occur due to parallax. Thus, each transparentelectrode and each corresponding reflective film is disposed opposingeach other via the insulating film. That is, a pair of conductors isdisposed on both sides of a dielectric. As a result, a capacitor isformed by these three elements. However, because the plurality ofconductive reflective films are not electrically connected to oneanother, the capacitors formed by the respective transparent electrodesare isolated from one another, and thus adjacent transparent electrodesare never capacitively coupled to each other via such capacitors andconductive reflective films. This effectively prevents image signalsapplied to the plurality of transparent electrodes from being mixedtogether or having cross-talk via capacitive coupling. Therefore, ahigh-quality image can be displayed in the reflective displaying modewithout producing waveform distortion.

The object described above can also be achieved by a third liquidcrystal device-according to the present invention. The third liquidcrystal device comprises: a pair of first and second substrates; aliquid crystal layer disposed between the first and second substrates; aplurality of transparent electrodes formed on a surface, on the side ofthe liquid crystal layer, of the second substrate; a plurality ofconductive transflective films which are formed between the plurality oftransparent electrodes and the second substrate in correspondence withthe respective plurality of transparent electrodes, the plurality oftransflective films being electrically isolated from each other; aninsulating film disposed between each of the plurality of transparentelectrodes and each of the plurality of transflective films; and anilluminating apparatus disposed on a side of the second substrate,opposite to the side where the liquid crystal layer is disposed.

In this third liquid crystal device according to the present invention,some part of ambient light input from the side of the first substratepasses through the transparent electrodes and such a part of light isreflected toward the liquid crystal layer by the:reflective films formedin the areas opposing the transparent electrodes, thereby forming animage in a reflective displaying mode. In this liquid crystal device,because the:reflective films are disposed on the surface, on the side ofthe liquid crystal layer, of the second substrate, there issubstantially no space between the reflective films and the liquidcrystal layer, and thus double images and dull images are prevented,which would otherwise occur due to parallax. On the other hand, in thetransmissive displaying mode, light emitted from the illuminatingapparatus and input from the side of the second substrate passes throughthe transflective films and the transparent electrodes into the side ofthe liquid crystal layer thereby displaying a high-brightness imageusing light source light in a dark environment. In this third liquidcrystal device, each transparent electrode and each correspondingreflective film are disposed opposing each other via the insulatingfilm. That is, a pair of conductors is disposed on both sides of adielectric. As a result, a capacitor is formed by these three elements.However, because the plurality of conductive reflective films are notelectrically connected to one another, the capacitors formed by therespective transparent electrodes are electrically isolated from oneanother, and thus adjacent transparent electrodes are never capacitivelycoupled to each other via such capacitors and conductive reflectivefilms. This effectively prevents image signals applied to the pluralityof transparent electrodes from being mixed together or having cross-talkvia capacitive coupling. Therefore, a high-quality image can bedisplayed in the reflective displaying mode without producing waveformdistortion.

The transflective films may be formed, for example, by disposing aplurality of reflective films such that they are spaced a predetermineddistance away from each other or by forming small openings in therespective reflective films such that the ratio of each opening area toeach reflective film area has a predetermined value. The insulating filmmay be formed by oxidizing the surface of the reflective films or bydisposing two or more different insulating films into a multilayerstructure. In many cases, the voltage vs. reflectance (transmittance)characteristic of the liquid crystal cell in the reflective displayingmode is different from that in the transmissive displaying mode.Therefore, it is desirable that the driving voltage in the reflectivedisplaying mode and the driving voltage in the transmissive displayingmode be set to different values optimized independently of each other.

In one mode of the second or third liquid crystal device according tothe present invention, there is further provided image signal supplyingmeans disposed on the second substrate, for supplying an image signal tothe plurality of transparent electrodes.

In this mode, image signals are preferably supplied to the transparentelectrodes by the image signal supplying means including, for example, adata line, a sampling circuit, a data line driving circuit, or the like.The image signals have a complicated waveform and a high drivingfrequency compared with other signals such as a scanning signal.Therefore, if the image signals mix with one another or have cross-talkwith one another via capacitive coupling as described earlier, largedistortion in waveforms occurs. However, in this mode, because theplurality of conductive reflective films are not electrically connectedto one another, image signals are effectively prevented from being mixedtogether or having cross-talk via capacitive coupling.

In another mode of the second or third liquid crystal device accordingto the present invention, there are further provided a plurality ofswitching elements disposed on the second substrate and connected to theplurality of transparent electrodes, respectively.

In this mode, image signals are supplied to the respective transparentelectrodes via switching elements such as TFTs (thin film diodes) orTFDs (thin film diodes) and a high-quality image is displayed by meansof active addressing.

Various known addressing methods are applicable to the above-describedthird liquid crystal devices according to the present invention. Theyinclude a passive matrix addressing method, a TFT active matrixaddressing method, a TFD active matrix addressing method, and a segmentaddressing method. The transparent electrode on the second substrate maybe formed into a proper shape such as a plurality of stripes or segmentsdepending on the addressing method. On the first substrate, a pluralityof stripe-shaped or segment-shaped transparent electrodes may be formed,or a single transparent electrode may be formed over the substantiallyentire surface of the first substrate. Alternatively, instead of formingthe opposite electrode on the first substrate, addressing may beperformed using an electric field generated between some transparentelectrodes on the second substrate in a horizontal direction parallel tothe substrate. Furthermore, in the first to third liquid crystaldevices, a polarizer, a retardation plate, and other elements aredisposed on a side, opposite to the liquid crystal layer, of the firstor second substrate as required depending on the addressing method.

The above-described object can also be achieved by a first electronicapparatus including the first liquid crystal device according to thepresent invention.

According to the first electronic apparatus of the present invention, itis possible to realize various types of electronic apparatuses using areflective liquid crystal device or a reflective color liquid crystaldevice capable of displaying, in a reflective displaying mode, ahigh-brightness and high-contrast image including no ghost and no dullimages due to parallax.

The above-described object can also be achieved by a second electronicapparatus including the second liquid crystal device according to thepresent invention.

According to the second electronic apparatus of the present invention,it is possible to realize various types of electronic apparatuses usinga reflective liquid crystal device or a reflective color liquid crystaldevice capable of displaying, in a reflective displaying mode, ahigh-brightness and high-contrast image including no ghost and no dullimages due to parallax.

The above-described object can also be achieved by a third electronicapparatus including the third liquid crystal device according to thepresent invention.

According to the third electronic apparatus of the present invention, itis possible to realize various types of electronic apparatuses using atransflective liquid crystal device or a transflective color liquidcrystal device capable of displaying, in both a reflective displayingmode and a transmissive fashion, a high-brightness and high-contrastimage including no ghost and no dull images due to parallax. The firstto third electronic apparatuses can display a high-quality image withoutbeing affected by ambient light regardless of whether it is used in alight or dark environment.

These and other features and advantages of the present invention willbecome more apparent from the following detailed description referringto preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a longitudinal sectional view schematically illustrating thestructure of a liquid crystal device according to a first embodiment ofthe present invention.

FIG. 2 a is a diagram schematically illustrating the manner in whichambient light is reflected by a reflective film via a transparentelectrode in a comparative example.

FIG. 2 b is a diagram schematically illustrating the manner in whichambient light is reflected by a reflective film via a transparentelectrode in the first embodiment.

FIG. 3 is a longitudinal sectional view illustrating the generalstructure of a liquid crystal device according to a second embodiment ofthe present invention.

FIG. 4 is a longitudinal sectional view illustrating the generalstructure of a liquid crystal device according to a third embodiment ofthe invention.

FIG. 5 is a plan view illustrating an example of a transflective filmformed of reflective films spaced from one another, used in the liquidcrystal device according to the third embodiment of the invention.

FIG. 6 is a plan view illustrating another example of a transflectivefilm formed of reflective films spaced from one another, used in thethird embodiment.

FIG. 7 is a longitudinal sectional view illustrating the generalstructure of a liquid crystal device according to a fourth embodiment ofthe invention.

FIG. 8 is a longitudinal sectional view illustrating the generalstructure of a liquid crystal device according to a fifth embodiment ofthe invention.

FIG. 9 is a longitudinal sectional view illustrating the generalstructure of a liquid crystal device according to a sixth embodiment ofthe invention.

FIG. 10 a is a schematic diagram illustrating the relationship in termsof rubbing directions among a polarizer, a retardation plate and aliquid crystal cell of a sixth embodiment.

FIG. 10 b is a graph illustrating the reflectance R and transmittance Tvs. driving voltage characteristic of the liquid crystal device underthe conditions shown in FIG. 10 a.

FIG. 11 is a cross-sectional view illustrating in an enlarged fashion aTFT driving device and other elements such as a pixel electrodeaccording to a seventh embodiment of the invention.

FIG. 12 is a cross-sectional view illustrating in an enlarged fashion aTFD driving device and other elements such as a pixel electrodeaccording to an eighth embodiment of the invention.

FIG. 13 is a graph illustrating the light transmittance of therespective colored layers of the color filter employed in the respectiveembodiments.

FIG. 14 is a perspective view schematically illustrating variouselectronic apparatuses according to a ninth embodiment of the presentinvention.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention is further described below with reference to bestmodes for respective embodiments in conjunction with the accompanyingdrawings.

First Embodiment

A first embodiment of a liquid crystal device according to the presentinvention is described below with reference to FIGS. 1-2 b. FIG. 1 is alongitudinal sectional view schematically illustrating the structure ofthe first embodiment of the liquid crystal device according to thepresent invention. Although this embodiment is basically concerned witha passive matrix type liquid crystal device, the structure disclosedherein may also be applied to other types of liquid crystal devices suchas an active matrix type device, a segment type device, etc.

In this reflective liquid crystal device of the first embodiment, asshown in FIG. 1, there is provided a liquid crystal cell including aliquid crystal layer 103 sealed between two transparent substrates 101and 102 and within a frame-shaped sealing member 104. The liquid crystallayer 103 is formed of a nematic liquid crystal with a particulartwisted angle. A color filter 113 is formed on the inner surface of theupper transparent substrate 101. The color filter 113 includes threecolored layers of R (red), G (green), and B (blue) with predeterminedpatterns. The surface of the color filter 113 is coated with atransparent protective film 112. A plurality of stripe-shapedtransparent electrodes 111 are formed of an ITO (indium tin oxide) filmor the like on the surface of this protective film 112. An alignmentlayer 110 is formed over the surface of the transparent electrodes 111and subjected to a rubbing process in a predetermined direction.

On the inner surface of the lower transparent or opaque substrate 102, aplurality of stripe-shaped transparent electrodes 115 are formed onrespective stripe-shaped reflective films 116,formed at locationscorresponding to the respective colored layers of the color filter 113described above, in such a manner that the transparent electrodes 115cross the transparent electrodes 111.

In the case of an active matrix type device including TFDs or TFTs, eachtransparent electrode 115 is formed in a rectangular shape and connectedto an interconnection via an active device.

The reflective films 116 are formed of a material such as Cr (chromium),Al (aluminum), or Ag (silver), and the surface thereof serves as areflection plane for reflecting light incident from the side of thetransparent substrate 101. Over the surface of the transparentelectrodes 115, an alignment layer 114 is formed and subjected to arubbing process in a predetermined direction.

In this first embodiment, as described above, the transparent electrodes115 are spaced from each other when they are viewed from a directionperpendicular to the substrate. The reflective films 116 are formedbetween the respective transparent electrodes 115 and the substrate 102in areas opposing the transparent electrodes 115 and no reflective filmis formed in spaces between the adjacent transparent electrodes 115.

Referring now to FIG. 2 a and FIG. 2 b, reflection of ambient lightperformed, in this first embodiment, by the transparent electrodes 115laminated on the reflective films 116 is described below. FIG. 2 a showsa comparative example including stripe-shaped transparent electrodes115′ formed on an insulating film 117′ on a reflective film 116′ whichis formed on a substrate over its entire surface, wherein the manner inwhich ambient light is reflected by the reflecting electrode 116′ isschematically illustrated. FIG. 2 b is a diagram schematicallyillustrating a manner of reflecting ambient light by the transparentelectrodes 115 laminated on the reflective films 116 according to thefirst embodiment.

In the comparative example, as shown in FIG. 2 a, ambient light L1 isreflected by the reflective film 116′ via the transparent electrodes115′ in respective pixels. This means that those parts of the liquidcrystal through which ambient light L1 passes can be effectively drivenby the transparent electrode 116′. However, ambient light L2 passingthrough the spaces between adjacent transparent electrodes 115′ (thatis, the spaces between adjacent pixels) is reflected by the reflectivefilm 116′ and output, in mixture with ambient light L1 which makescontribution to forming an image, to the outside of the liquid crystaldevice without making contribution to displaying the image (instead,ambient light L2 causes a reduction in the contrast ratio of thedisplayed image). As a result, degradation in display quality occurs.

In contrast, in the first embodiment, as shown in FIG. 2 b, ambientlight L1 is reflected by the reflective films 116 via the transparentelectrodes 115 in respective pixels, wherein the reflective films 116are formed in the areas opposing the transparent electrodes 115 but notformed in spaces between adjacent transparent electrodes 115. Therefore,those parts of the liquid crystal through which ambient light L1 passescan be effectively driven by the transparent electrodes 116. In thepresent embodiment, ambient light L2 passing through spaces betweenadjacent transparent electrodes 115 (that is, spaces between adjacentpixels) further passes through spaces between adjacent reflective films116. Therefore, in this case, no ambient light L2 is output, in mixturewith ambient light L1 making contribution to displaying an image, to theoutside of the liquid crystal device without making any contribution todisplaying the image (instead, such ambient light L2 would cause areduction in the contrast ratio of the displayed image). Therefore, asopposed to the comparative example, no degradation occurs in the imagequality due to light passing through spaces between adjacentstripe-shaped or island-shaped transparent electrodes. In the presentembodiment, each transparent electrode 115 and each correspondingreflective film 116 may be equal in size, or each transparent electrode115 may be slightly greater in size than each corresponding reflectivefilm 116. No reflective film 116 may be formed in some spaces betweenadjacent transparent electrodes 115 whereas reflective films 116 may beformed in the other spaces between adjacent transparent electrodes 115.Alternatively, instead of spacing the reflective films 116 from eachother, openings may be formed in a single reflective film 116, in areascorresponding to the spaces between adjacent transparent electrodes.However, because those portions of the reflective films 116 on whichthere is no overlapping transparent electrode 115 do not contribute toforming an image (but result in a reduction in the contrast ratio), theyare basically unnecessary. To effectively utilize an image displayingarea limited in size, it is desirable to design the layout in ahorizontal plane such as to minimize the portions of the reflectivefilms 116 on which there is no overlapping transparent electrode 115.

Referring again to FIG. 1, a polarizer 105 is disposed on the outersurface of the upper transparent substrate 101, and a retardation plate106 and a scattering plate 107 are disposed between the polarizer 105and the transparent substrate 101. Light reflected by the Al reflectivefilms 116 is output to the outside after being diffused by thescattering plate 107 over a wide angle range. Thus, the scattering plate107 allows the reflective films 116 having a mirror surface to serve ineffect as a scattering surface (white surface). The scattering plate 107may be disposed at any location as long as it is on the opposite side ofthe transparent substrate 101 to the side on which the liquid crystallayer 103 is located. However, if the back scattering effect (the effectof scattering incident ambient light toward the side from which light isincident) of the scattering plate 107 is taken into account, it isdesirable to dispose the scattering plate 107 between the polarizer 105and the transparent substrate 101 as in the present embodiment. In thereflective liquid crystal device, such back scattering does not make anycontribution to displaying an image but causes a reduction in thecontrast. If the scattering plate 107 is disposed between the polarizer105 and the transparent substrate 101, the amount of back-scatteredlight is reduced by the polarizer 105 by approximately half.

Referring to FIG. 1, the operation of displaying an image performed bythe reflective liquid crystal device of the present embodiment isdescribed below.

Ambient light incident from the upper side in FIG. 1 onto the liquidcrystal device passes through the polarizer 105, the retardation plate106, and the scattering plate 107. The light further passes through thecolor filter 113 and the liquid crystal layer 103 and is then reflectedby the reflective films 116. The reflected light is output to theoutside via the polarizer 105. In this reflective displaying mode, theintensity of output light is controlled to a bright, dark, orintermediate level in response to the voltage applied to the liquidcrystal layer 103.

The structure according to the present embodiment makes it possible torealize a color liquid crystal device capable of displaying an imagewithout producing double images or a dull images. In the presentembodiment, some part of ambient light incident from the side of thetransparent substrate 101 passes through the spaces between adjacenttransparent electrodes 115. However, such light is never reflected bythe reflective films 116 toward the liquid crystal layer 103, and thusdegradation in the image quality is suppressed.

In the present embodiment, the color filter 113 is formed such that itscolored areas are located opposing the transparent electrodes 115.However, the color filter 113 has no light shielding areas at locationscorresponding to the spaces between adjacent transparent electrodes 115.Therefore, ambient light can pass through the spaces between adjacentcolored areas. However, in the spaces between adjacent colored areas,there is no reflective film 116, which reflects such light. Thisprevents mixing of colors between adjacent colored areas of the colorfilter 113, which would otherwise occur due to reflection by thereflective films 116. Thus, a color image is prevented from having dullimages or blurring due to mixing of colors. On the other hand, theabove-described structure of the color filter 113 including no lightshielding area results in an increase in brightness of the imagedisplayed in the reflective displaying mode.

The color filter 113 may be formed such that there is no light shieldingarea in any space between colored areas or such that there are lightshield areas in some spaces between colored areas. Furthermore, thecolor filter may be disposed on the transparent substrate 101 asdescribed above or may be disposed together with the reflective films116, the insulating film, the color filter, and the transparentelectrodes 115 into a multilayer structure on the substrate 102 suchthat the color filter 113 is located between the layers of theinsulating film and the transparent electrodes 115. Instead, the colorfilter 113 may be disposed together with the reflective films 116, theinsulating film, the protective film, and the transparent electrodes 115into a multilayer structure such that the color filter is locatedbetween the layers of the insulating film and the protective film.

Furthermore, in the present embodiment, because the transparentelectrodes 115 are formed directly on the reflective films 116, both theAl reflective films 116 and the ITO transparent electrodes 115 serve aselectrode lines. This results in a reduction in resistance of eachelectrode line. Preferably, each reflective film 116 contains 95 wt% ormore aluminum and has a thickness in the range from 10 nm to 40 nm.

Furthermore, the scattering plate 107 disposed on the upper surface ofthe liquid crystal cell serves to output light reflected by the Alreflective films 116 such that the light is diffused over a wide rangeof angles. This makes it possible to realize a liquid crystal devicewith a wide viewing angle.

Second Embodiment

A second embodiment of a liquid crystal device according to the presentinvention is described below with reference to FIG. 3. FIG. 3 is alongitudinal sectional view illustrating the structure of the liquidcrystal device according to the second embodiment of the invention. Thisthird embodiment is similar in construction to the first embodimentdescribed above except that transparent electrodes and reflective filmsare formed in a different structure. In FIG. 3, similar constituentelements to those in the first embodiment described above with referenceto FIG. 1 are denoted by similar reference numerals, and thereby theywill be omitted.

In th e reflective liquid crystal device of the second embodiment, asshown in FIG. 3, an insulating film 117 is formed between eachreflective film 116 and each transparent electrode 115. The other partsare similar to those of the first embodiment. An example of the processof forming the insulating film 117 is described below.

First, reflective films are formed into the shape of islands or stripescorresponding to the respective dots by evaporating, for example,aluminum to a thickness of 50 nm to 300 nm. The reflective films arethen anodized so as to form Al₂O₃(aluminum oxide) serving as theinsulating layer on the surface of the reflective films. The anodizationmay be performed using a solution containing 1-10 wt % ammoniumsalicylate and 20-80 wt % ethylene glycol under conditions of aformation voltage of 5 to 250 V and a current density of 0.001 to 0.1mA/cm². T his technique makes it possible to form the insulating film,which is very thin and highly resistant. If the thickness of the oxidefilm is selected to be equal to 140 nm or an integral multiple of thisvalue, then coloring due to interference can be prevented. By employingaluminum as a material for forming the reflective films, it becomespossible to maintain a high reflectance after the oxidation. Theformation of the insulating film by means of oxidation may also beperformed using thermal oxidation. The insulating film may be formed ina multilayer structure consisting of a plurality of insulating filmlayers. More specifically, after forming an oxide film by anodizing areflective film of metal, an upper insulating film may be formed bycoating an organic material on the oxide film using a spin-coatingtechnique, or a SiO₂ film or the like may be evaporated on the oxidefilm.

Thus, in this second embodiment, each transparent electrode 115 and eachcorresponding reflective film 116 are disposed opposing each other via acorresponding insulating film 117. That is, a pair of conductors aredisposed on both sides of a dielectric. As a result, a capacitor isformed by these three elements. If the respective reflective films 116are electrically connected to one another, adjacent transparentelectrodes 115 are capacitively coupled to each other via capacitorsformed in the above-described manner and via the conductive reflectivefilms 116. In this second embodiment, however, because the plurality ofconductive reflective films 116 are not electrically connected to oneanother, the capacitors corresponding to the respective transparentelectrodes 115 are isolated from one another, and thus such capacitivecoupling does not occur. This prevents image signals applied to theplurality of transparent electrodes 115 from being mixed together orhaving cross-talk via capacitive coupling. Therefore, a high-qualityimage can be displayed in the reflective displaying-mode withoutproducing waveform distortion.

In this second embodiment, image signals are preferably supplied to thetransparent electrodes 115 via data lines, a sampling circuit, a dataline driving circuit, or the like. The image signals have a complicatedwaveform and a high driving frequency compared with other signals suchas a scanning signal. However, because the plurality of conductivereflective films 116 are not electrically connected to each other, imagesignals are effectively prevented from being mixed together or havingcross-talk via capacitive coupling. In contrast, the scanning signal hasa rather simple waveform and a low driving frequency. Therefore,significant signal degradation due to the coupling does not occur.

Furthermore, in this second embodiment, because the insulating films 117are disposed between the respective transparent electrodes 115 and thecorresponding reflective films 116, the reflective films 116 are allowedto be formed of an conductive material such as Al without causingelectrical leakage or short circuits among the plurality of transparentelectrodes 115 via the reflective films 116. This also allows thepattern, in the horizontal plane, of the reflective films 116 to bedesigned in a more flexible fashion.

As described above, the structure according to the present embodimentmakes it possible to realize a color liquid crystal device capable ofdisplaying an image with a high brightness and a high contrast in areflective displaying mode without producing dull images or doubleimages.

Third Embodiment

A third embodiment of a liquid crystal device according to the presentinvention is described below with reference to FIGS. 4 to 6. FIG. 4 is alongitudinal sectional view schematically illustrating the structure ofthe third embodiment of the liquid crystal device according to thepresent invention. Although this embodiment is basically concerned witha passive matrix type liquid crystal device, the structure disclosedherein may also be applied to other types of liquid crystal devices suchas an active matrix type device, a segment type device, etc.

In the transflective liquid crystal device of the third embodiment, asshown in FIG. 4, there is provided a liquid crystal cell including aliquid crystal layer 203 sealed between two transparent substrates 201and 202 and within a frame-shaped sealing member 204. The liquid crystallayer 203 is formed of a nematic liquid crystal with a particulartwisted angle. A color filter 213 is formed on the inner surface of theupper transparent substrate 201. The color filter 213 includes threecolored layers of R (red), G (green), and B (blue) with predeterminedpatterns. The surface of the color filter 213 is coated with atransparent protective film 212. A plurality of stripe-shapedtransparent electrodes 211 are formed of an ITO (indium tin oxide) filmor the like on the surface of this protective film 212. An alignmentlayer 210 is formed over the surface of the transparent electrodes 211and subjected to a rubbing process in a predetermined direction.

On the inner surface of the lower transparent substrate 202,stripe-shaped transparent electrodes 215 slightly greater in area thanthe reflective films 216 are formed on the stripe-shaped reflectivefilms 216 formed at locations corresponding to the respective coloredlayers of the color filter 213 described above, in such a manner thatthe transparent electrodes 215 cross the transparent electrodes 211.

In the case of an active matrix type device including TFDs or TFTs, eachtransparent electrode 215 is formed in a rectangular shape and connectedto an interconnection via an active device.

The reflective film 216 is formed of Cr. Al, Ag, or the like, and thesurface thereof serves as a reflection plane for reflecting lightincident from the side of the transparent substrate 201. On the surfaceof the transparent electrode 215, an alignment layer 214 is formed andsubjected to a rubbing process in a predetermined direction.

Thus, in this third embodiment, the plurality of reflective films 216are arranged in a stripe fashion such that they are spaced apredetermined distance apart from each other so that the spaces betweenadjacent reflective films 216 serve to pass light emitted from abacklight. Preferably, the reflective films 216 are spaced from eachother by a distance in the range from 0.01 μm to 20 μm so that thespaces are not easily perceived by users and thus degradation in imagequality due to the spaces is minimized, thereby allowing an image to bedisplayed in both reflective and transmissive modes. Furthermore, it isdesirable that the ratio of the area of each space between adjacentreflective films 216 to the area of each reflective film 216 is set to avalue in the range of 5% to 30% so that the reduction in the brightnessis minimized in the reflective displaying mode whereas an image is alsoallowed to be displayed in the transmissive mode using light suppliedvia the spaces between reflective films.

Referring to FIG. 4, a polarizer 205 is disposed on the outer surface ofthe upper transparent substrate 201, and a retardation plate 206 and adiffusing plate 207 are disposed between the polarizer 205 and thetransparent substrate 201. On the lower side of the liquid crystal cell,a retardation plate 209 is disposed at the back of the transparentsubstrate 202, and a polarizer 208 is disposed at the back of theretardation plate 209. Furthermore, on the lower side of the polarizer208, there is disposed a backlight including a fluorescent tube 218 foremitting white light and a light guiding plate 217 having a lightincident end face extending along the fluorescent tube 218. The lightguiding plate 217 is formed of a transparent material such as acrylicresin in such a manner that its entire back surface becomes rough so asto serve as a scattering surface. Light emitted from the fluorescenttube 218 serving as a light source is input into the light guiding plate217 through its end face, and light is output substantially uniformlythrough the upper surface. Other types of backlights such as an LED(light emitting diode) or an EL (electroluminescence) lamp may also beemployed.

Light reflected by the Al reflective films 216 is output to the outsideafter being scattered by the scattering plate 207 over a wide range ofangles. Thus, the scattering plate 207 allows the reflective films 216having a mirror surface to serve in effect as a scattering surface(white surface). The scattering plate 207 may be disposed at anylocation as long as it is on the opposite side of the transparentsubstrate 201 to the side on which the liquid crystal layer 203 islocated. However, if the back scattering effect (the effect ofscattering incident ambient light toward the side from which light isincident) of the scattering plate 207 is taken into account, it isdesirable to dispose the scattering plate 207 between the polarizer 205and the transparent substrate 201 as in the present embodiment. In thereflective liquid crystal device, such back scattering does not make anycontribution to displaying an image but causes a reduction in thecontrast. If the scattering plate 207 is disposed between the polarizer205 and the transparent substrate 201, the amount of back-scatteredlight is reduced by the polarizer 205 by approximately half.

In this third embodiment, as described above, the polarizer 205 and theretardation plate 206 are disposed on the upper side of the liquidcrystal cell, and the polarizer 208 and the retardation plate 209 aredisposed on the lower side of the liquid crystal cell so that ahigh-quality image can be displayed in both the reflective andtransmissive modes. More specifically, the retardation plate 206suppresses the effects of wavelength dispersion of light, such ascoloring, upon the color tone in the reflective displaying mode (thatis, the retardation plate 206 serves to optimize the displayingconditions in the reflective displaying mode), and furthermore, theretardation plate 209 also suppresses the effects of wavelengthdispersion of light, such as coloring, upon the color tone in thetransmissive displaying mode (that is, the retardation plate 206 servesto optimize the displaying conditions in the transmissive displayingmode under the conditions where the displaying conditions in thereflective displaying mode is optimized by the retardation plate 209).It desired, a plurality of retardation plates 206 or 209 may be disposedso as to compensate for coloring of the liquid crystal cell orcompensate for the viewing angle. By disposing a plurality ofretardation plates 206 or 209, it becomes easier to optimizecompensation for coloring or the viewing angle. Furthermore, it alsobecomes possible to adjust the optical conditions associated with thepolarizer 205, the retardation plate 106, the liquid crystal layer 103,and the reflective films 216 such as to increase the contrast in thereflective displaying mode, and further adjust, under the aboveconditions, the optical conditions associated with the polarizer 208 andthe retardation plate 209 such as to increase the contrast in thetransmissive displaying mode, thereby achieving a high contrast in boththe reflective and transmissive displaying modes.

Referring to FIG. 4, the operation of displaying an image in reflectiveand transmissive modes according to the present embodiment is describedbelow.

In the reflective displaying mode, ambient light incident from the upperside in FIG. 4 onto the liquid crystal device passes through thepolarizer 205, the retardation plate 206, and the scattering plate 207.The light further passes through the color filter 213 and the liquidcrystal layer 203 and is then reflected by the reflective films 216. Thereflected light is output to the outside via the polarizer 205. In thisreflective displaying mode, the intensity of output light is controlledto a bright, dark, or intermediate level in response to the voltageapplied to the liquid crystal layer 203.

In the case where an image is displayed in the transmissive displayingmode, light emitted from the backlight is converted by the polarizer 208and the retardation plate 209 into light with predetermined polarizationand introduced into the liquid crystal layer 203 and the color filter213 via spaces where no reflective film 216 is formed. After that, thelight passes through the diffusing plate 207 and the retardation plate206. In this transmissive displaying mode, the light transmission iscontrolled by the voltage applied across the liquid crystal layer 203into a state where the light passes through the polarizer 205 (brightstate) or a state where the light is absorbed by the polarizer 205 (darkstate) or otherwise into an intermediate state (with intermediatebrightness).

The operation of displaying an image is described in further detailbelow for both the reflective displaying mode and the transmissivedisplaying mode with reference to FIGS. 5 and 6. FIG. 5 is a front viewschematically illustrating a lower transparent substrate 202 used in anactive matrix type liquid crystal device including TFDs according to thepresent invention. TFDs 502 are formed above the respectiveisland-shaped Al reflective films 503 and connected to a scanning line501 and also to the corresponding ITO transparent electrodes 504 havinga slightly greater area than the Al reflective films 503. FIG. 6 is afront view schematically illustrating an example of a lower transparentsubstrate 202 used in a passive matrix type liquid crystal deviceaccording to the present invention. Al reflective films 602 andstripe-shaped ITO transparent electrodes 603 having a slightly greaterarea than the reflective films 602 are formed on the inner surface ofthe lower transparent substrate such that they cross stripe-shaped ITOtransparent electrodes 601 formed on the inner surface of an uppertransparent substrate of a liquid crystal cell.

In the reflective displaying mode, ambient light input into the liquidcrystal cell is reflected by the reflective films 503 (in the case ofFIG. 5) or the reflective films 602 (in the case of FIG. 6). That is, ofthe ambient light, only the part, which is incident on the reflectivefilms 503 or 602, is modulated according to the voltage applied acrossthe liquid crystal layer. In the transmissive displaying mode, of lightinput from the backlight into the liquid crystal cell, only the part,which passes through the reflective films 503 or 602, is introduced intothe liquid crystal layer. However, light incident upon areas other thanthe pixel electrodes or the dot electrodes does not make anycontribution to displaying an image but causes a reduction in thecontrast in the transmissive displaying mode. To avoid this problem,such light is blocked by providing a light shielding film (black matrixlayer) or by displaying the image in a normally black mode. That is, inthe transmissive displaying mode, an image is displayed by light inputfrom the backlight through the areas where there are only ITOtransparent electrodes 504 or 603 but there are no overlapping Alreflective films 503 or 602.

For example, if the ITO transparent electrodes 601 formed on the innersurface of the upper transparent substrate shown in FIG. 6 each have aline width (L) of 198 μm, the Al reflective films 602 formed on theinner surface of the lower substrate each have a line width (W1) of 46μm , and the ITO transparent electrodes 603 formed over the Alreflective films 602 each have a line width (W2) of 56 μm , thenapproximately 70% of ambient light introduced into the liquid crystallayer is reflected, and approximately 10% of light input from thebacklight into the lower transparent substrate is passed.

By employing the structure disclosed herein in the present embodiment,it is possible to realize a color liquid crystal device capable ofswitching the displaying mode between the reflective and transmissivemodes in any of which a high-brightness and high-contrast image can bedisplayed without producing double images or dull images.

Furthermore, in the present embodiment, because ambient light which haspassed through the spaces between adjacent transparent electrodes 315(that is, between adjacent pixel) further passes through the spacesbetween adjacent reflective films 316, ambient light which does not makeany contribution to displaying an image (but which causes a reduction inthe contrast of the image) does not emerge from the liquid crystaldevice in mixture with ambient light which makes contribution todisplaying the image. Therefore, no degradation occurs in the imagequality due to light passing through the spaces between stripe-shaped orisland-shaped transparent electrodes.

In the present embodiment, the color filter 213 is formed such that itscolored areas are located opposing the transparent electrodes 215.However, the color filter 213 has no light shielding areas at locationscorresponding to the spaces between adjacent transparent electrodes 215.Therefore, ambient light can pass through the spaces between adjacentcolored areas. However, in the spaces between adjacent colored areas,there is no reflective film 216, which reflects such light. Therefore,mixing of colors between adjacent colored areas of the color filter 213is prevented, which would otherwise occur due to reflection by thereflective films 216. Thus, a color image is prevented from having dullimages or blurring due to mixing of colors. The absence of such a lightshielding area results in an improvement in the image brightness in thereflective displaying mode.

Furthermore, in the present embodiment, because the transparentelectrodes 215 are formed directly on the reflective films 216, both theAl reflective films 216 and the ITO transparent electrodes 215 serve aselectrode lines. This results in a reduction in resistance of eachelectrode line. Still furthermore, because the Al reflective films 216are covered with the corresponding ITO transparent electrodes 215, theAl reflective films 216 are prevented from being damaged. Stillfurthermore, because both the Al reflective films 216 and the ITOtransparent electrodes 215 serve as electrode lines, a reduction inresistance is achieved for each electrode line. Preferably, eachreflective film 216 contains 95 wt % or more aluminum and has athickness in the range from 10 nm to 40 nm.

Furthermore, the scattering plate 207 disposed on the upper surface ofthe liquid crystal cell serves to output light reflected by the Alreflective films 216 such that the light is scattered over a wide rangeof angles. This makes it possible to realize a liquid crystal devicewith a wide viewing angle.

Fourth Embodiment

A fourth embodiment of a liquid crystal device according to the presentinvention is described below with reference to FIG. 7. FIG. 7 is alongitudinal sectional view illustrating the general structure of aliquid crystal device according to a fourth embodiment of the invention.Although this embodiment is basically concerned with a passive matrixtype liquid crystal device, the structure disclosed herein may also beapplied to other types of liquid crystal devices such as an activematrix type device, a segment type device, etc.:

In the transflective liquid crystal device of the fourth embodiment, asin the third embodiment, there is provided a liquid crystal cellincluding a liquid crystal layer 303 sealed between two transparentsubstrates 301 and 302 and within a frame-shaped sealing member 304. Theliquid crystal layer 303 is formed of a nematic liquid crystal with aparticular twisted angle. A color filter 313 is formed on the innersurface of the upper transparent substrate 301. The color filter 313includes three colored layers of R, G, and B with predeterminedpatterns. The surface of the color filter 313 is coated with atransparent protective film 312. A plurality of stripe-shapedtransparent electrodes 311 are formed of ITO or the like on the surfaceof this protective film 312. An alignment layer 310 is formed over thesurface of the transparent electrodes 311 and subjected to a rubbingprocess in a predetermined direction.

On the inner surface of the lower transparent substrate 302,stripe-shaped transparent electrodes 315 slightly greater in area thanthe reflective films 317 are formed, via a protective film 316, on thestripe-shaped reflective films 317 formed at locations corresponding tothe respective colored layers of the color filter 313 described above,wherein a plurality of such transparent electrodes 315 are disposed suchthat they cross the transparent electrodes 311. In the case of an activematrix type device including TFDs or TFTs, each reflective film 317 andeach transparent electrode 315 are formed in rectangular shapes andconnected to interconnections via active devices. The reflective film317 is formed of Cr, Al, Ag, or the like, and the surface thereof servesas a reflection plane for reflecting light incident from the side of thetransparent substrate 301. On the surface of the transparent electrode315, an alignment layer 314 is formed and subjected to a rubbing processin a predetermined direction.

Thus, in this fourth embodiment, the plurality of reflective films 317are arranged in a stripe fashion such that they are spaced apredetermined distance apart from each other so that the spaces betweenadjacent reflective films 317 serve to pass light emitted from abacklight.

A polarizer 305 is disposed on the outer surface of the uppertransparent substrate 301, and a retardation plate 306 and a scatteringplate 307 are disposed between the polarizer 305 and the transparentsubstrate 301. On the lower side of the liquid crystal cell, aretardation plate 309 is disposed at the back of the transparentsubstrate 302, and a polarizer 308 is disposed at the back of theretardation plate 309. Furthermore, on the lower side of the polarizer308, there is disposed a backlight including a fluorescent tube 319 foremitting white light and a light guiding plate 318 having a lightincident end face extending along the fluorescent tube 319. The lightguiding plate 318 is formed of a transparent material such as acrylicresin in such a manner that its entire back surface becomes rough so asto serve as a scattering surface. Light emitted from the fluorescenttube 319 serving as a light source is input into the light guiding plate318 through its end face, and light is output substantially uniformlythrough the upper surface. Other types of backlights such as an LED(light emitting diode) or an EL (electroluminescence) lamp may also beemployed.

Referring to FIG. 7, the operation of displaying an image in reflectiveand transmissive modes according to the present embodiment is describedbelow.

In the reflective displaying mode, ambient light incident from the upperside in FIG. 7 onto the liquid crystal device passes through thepolarizer 305, the retardation plate 306, and the scattering plate 307.The light further passes through the color filter 313 and the liquidcrystal layer 303 and is then reflected by the reflective films 317. Thereflected light is output to the outside via the polarizer 305. In thisreflective displaying mode, the image brightness can be controlled bythe voltage applied across the liquid crystal layer 303 into a bright,dark, or intermediate state.

In the case where an image is displayed in the transmissive displayingmode, light emitted from the backlight is converted by the polarizer 308and the retardation plate 309 into light with predetermined polarizationand introduced into the liquid crystal layer 303 and the color filter313 via spaces where no reflective film 317 is formed. After that, thelight passes through the scattering plate 307 and the retardation plate306. In this transmissive displaying mode, the light transmission iscontrolled by the voltage applied across the liquid crystal layer 303into a state where the light passes through the polarizer 305 (brightstate) or a state where the light is absorbed by the polarizer 305 (darkstate) or otherwise into an intermediate state (with intermediatebrightness).

The transparent electrodes 315 and the reflective films 317 may beformed, as in the third embodiment, into the shape in the horizontalplane as shown in FIG. 5 for the case of an active matrix type liquidcrystal device using TFDs or into the shape as shown in FIG. 6 for thecase of a passive matrix type liquid crystal device.

For example, if the ITO transparent electrodes 601 formed on the innersurface of the upper transparent substrate shown in FIG. 6 each have aline width (L) of 240 μm, the Al reflective films 602 formed on theinner surface of the lower substrate each have a line width (W1) of 60μm, and the ITO transparent electrodes 603 formed over the Al reflectivefilms 602 each have a line width (W2) of 70 μm, then approximately 75 %of ambient light introduced into the liquid crystal layer is reflected,and approximately 8% of light input from the backlight into the lowertransparent substrate is passed.

By employing the structure disclosed herein in the present embodiment,it is possible to realize a color liquid crystal device capable ofswitching the displaying mode between the reflective and transmissivemodes in any of which an image can be displayed without producing doubleimages or dull images.

Thus, in this fourth embodiment, each transparent electrode 315 and eachcorresponding reflective film 317 are disposed opposing each other viathe protective film 316. That is, a pair of conductors are disposed onboth sides of a dielectric. As a result, a capacitor is formed by thesethree elements. If the respective reflective films 316 are electricallyconnected to one another, adjacent transparent electrodes 315 arecapacitively coupled to each other via capacitors formed in theabove-described manner and via the conductive reflective films 317. Inthis fourth embodiment, however, because the plurality of conductivereflective films 317 are not electrically connected to one another, thecapacitors corresponding to the respective transparent electrodes 315are isolated from one another, and thus such capacitive coupling doesnot occur. This prevents image signals applied to the plurality oftransparent electrodes 315 from being mixed together or havingcross-talk via capacitive coupling. Therefore, a high-quality image canbe displayed in the reflective displaying mode without producingwaveform distortion.

In this fourth embodiment, image signals are preferably supplied to thetransparent electrodes 315 via data lines, a sampling circuit, a dataline driving circuit, or the like. The image signals have a complicatedwaveform and a high driving frequency compared with other signals suchas a scanning signal. However, because the plurality of conductivereflective films 317 are electrically isolated from one another, imagesignals are effectively prevented from being mixed together or havingcross-talk via capacitive coupling.

Furthermore, in this fourth embodiment, because the protective film 316is disposed between the respective transparent electrodes 315 and thecorresponding reflective films 317, the reflective films 317 are allowedto be formed of an conductive material such as Al without causingelectrical leakage or short circuits among the plurality of transparentelectrodes 315 via the reflective films 317. This also allows thepattern, in the horizontal plane, of the reflective films 317 to bedesigned in a more flexible fashion.

In this embodiment, after forming the protective film 316 over the Alreflective films 317, the ITO transparent electrodes 315 are formed onthe protective film 316. Therefore, the Al reflective films 317 areprevented from direct contact with a developing solution or an etchingused to form the ITO transparent electrodes 315. Furthermore, theprotective film 316 prevents the Al reflective films 317 from beingdamaged. By electrically connecting the Al reflective films 317 to theITO transparent electrodes 315, it becomes possible to reduce theprobability that electric disconnection occurs, and it also becomespossible to reduce the resistance of the electrode lines.

The scattering plate 307 disposed on the upper surface of the liquidcrystal cell serves to output light reflected by the Al reflective films317 such that the light is scattered over a wide range of angles. Thismakes it possible to realize a liquid crystal device with a wide viewingangle.

Fifth Embodiment

A fifth embodiment of a liquid crystal device according to the presentinvention is described below with reference to FIG. 8. FIG. 8 is alongitudinal sectional view illustrating the general structure of aliquid crystal device according to a fifth embodiment of the invention.This fifth embodiment is similar in construction to the fourthembodiment described above except that reflective films are formed intoa different structure. In FIG. 8, similar constituent elements to thosein the fourth embodiment described above with reference to FIG. 7 aredenoted by similar reference numerals, and thereby they will be omitted.

In the transflective liquid crystal device according to the fifthembodiment shown in FIG. 8, the reflective films 317′ are formed asfollows.

First, a photosensitive resist is coated on the inner surface of thetransparent substrate 302 using a spin coating technique or the like.The photosensitive resist is then exposed to light with controlledintensity through a mask having small openings. After that, thephotosensitive resist is baked as required and then developed so thatportions corresponding to the openings of the mask are removed therebyforming a supporting layer having a corrugated shape in cross section.In the above photolithography process, the portions of thephotosensitive resist corresponding to the openings of the mask may beremoved or left without being removed, and the uneven surface geometrymay be smoothed by means of etching or heating thereby achieving acorrugated shape in cross section. An additional layer may be formed onthe surface of the supporting layer so as to obtain a smoother surface.

A thin film of metal is then deposited on the surface of the supportinglayer by means of evaporation or sputtering thereby forming a metal filmhaving a reflection plane. The thin film is then patterned into theshape of stripes (refer to FIG. 6) or islands (refer to FIG. 5). Themetals, which can be employed here, include Al, Cr, Ag, and Au. Becausethe corrugated shape of the surface of the supporting layer is reflectedin the formation of the reflective films 317′, the reflective films 317′have a generally rough surface.

By employing the structure disclosed herein in the present embodiment,it is possible to realize a color liquid crystal device capable ofswitching the displaying mode between the reflective and transmissivemodes in any of which an image can be displayed without producing doubleimages or dull images.

In particular, the reflective films 317′ whose surface is made uneven iscapable of reflecting light over a wide range of angles. This makes itpossible to realize a liquid crystal device with a wide viewing angle.

Sixth Embodiment

A sixth embodiment of a liquid crystal device according to the presentinvention is described below with reference to FIGS. 9 to 10 b. FIG. 9is a longitudinal sectional view illustrating the general structure of aliquid crystal device according to a sixth embodiment of the invention.Although this embodiment is basically concerned with a passive matrixtype liquid crystal device, the structure disclosed herein may also beapplied to other types of liquid crystal devices such as an activematrix type device, a segment type device, etc.

In the transflective liquid crystal device of the sixth embodiment,there is provided a liquid crystal cell including a liquid crystal layer403 sealed between two transparent substrates 401 and 402 and within aframe-shaped sealing member 404. The liquid crystal layer 403 is formedof a nematic liquid crystal with negative dielectric anisotropy. Aplurality of stripe-shaped transparent electrodes 409 are formed of ITOor the like on the inner surface of the upper transparent substrate 401.An alignment layer 410 for aligning the liquid crystal in verticaldirection is formed over the transparent electrodes 409 and rubbed in apredetermined direction. The rubbing is performed so those liquidcrystal molecules have a pretilt angle of about 85° to the rubbingdirection. In the case of an active matrix type device including TFDs orTFTs, each transparent electrode 409 is formed in a rectangular shapeand connected to an interconnection via an active device.

On the other hand, a corrugation with a top-to-bottom height of about0.8 μm is formed of a photosensitive acrylic resin on the inner surfaceof the lower transparent substrate 402. Aluminum added with 1.0 wt % Ndis sputtered to a thickness of 25 nm onto the surface of the acrylicresign and patterned into the shape of stripes (refer to FIG. 6) orislands (refer to FIG. 5) thereby forming reflective films 411. A colorfilter 414 is formed over the reflective films 411 via a protective film412. The color filter 414 includes three colored layers of R, G, and Bwith predetermined patterns. The surface of the color filter 414 iscoated with a transparent protective film 415. A plurality ofstripe-shaped transparent electrodes 416 is formed of ITO or the like onthe surface of the protective films 415 such that they cross thetransparent electrodes 409 for the respective colored layers of thecolor filters 414. An alignment layer 417 is formed over the transparentelectrodes 416. This alignment layer 417 is not subjected to the rubbingprocess.

A polarizer 405 is disposed on the outer surface of the uppertransparent substrate 401, and a retardation plate (quarter-wavelengthplate) 406 is disposed between the polarizer 405 and the transparentsubstrate 401. On the lower side of the liquid crystal cell, aretardation plate (quarter-wavelength plate) 408 is disposed at the backof the transparent substrate 402, and a polarizer 407 is disposed at theback of the retardation plate (quarter-wavelength plate) 408.Furthermore, on the lower side of the polarizer 407, there is disposed abacklight including a fluorescent tube 419 for emitting white light anda light guiding plate 418 having a light incident end face extendingalong the fluorescent tube 419. The light guiding plate 418 is formed ofa transparent material such as acrylic resin in such a manner that itsentire back surface becomes rough or printed layer so as to serve as ascattering surface. Light emitted from the fluorescent tube 419 servingas a light source is input into the light guiding plate 418 through itsend face, and light is output substantially uniformly through the uppersurface. Other types of backlights such as an LED (light emitting diode)or an EL (electroluminescence) lamp may also be employed.

In the present embodiment, to prevent light from leaking through areasbetween adjacent dots in the transmissive displaying mode, a blackmatrix layer 413 serving as a light shielding member is formed in ahorizontal plane at locations corresponding to the spaces betweenadjacent colored areas of the color filter 414. The black matrix layer413 may be formed by coating a Cr layer or may be formed of aphotosensitive black resin.

Herein, as shown in FIG. 10 a, the polarizers 40S and 407 are disposedsuch that their polarization axes P1 and P2 extend in the samedirection. The retardation plates (quarter-wavelength plates) 406 and408 are disposed such that their delayed phase axes C1 and C2 extend ina direction rotated by θ=45° in a clockwise direction relative to thepolarization axes P1 and P2 of the polarizers 405 and 407. The alignmentlayer 410 on the inner surface of the transparent substrate 401 issubjected to a rubbing process in the direction R1 same as the delayedphase axes C1 and C2 of the retardation plates (quarter-wavelengthplates) 406 and 408. The rubbing direction R1 determines the directionin which long axes of liquid crystal molecules are tilted when anelectric field is applied across the liquid crystal layer 403. Anegative nematic liquid crystal is employed to form the liquid crystallayer 403.

FIG. 10 b is a graph illustrating the reflectance R and thetransmittance T as a function of the driving voltage obtained when theliquid crystal device according to the present embodiment is used in thereflective displaying mode. Herein, the liquid crystal device is in adark (black) state when no electric field is applied. When this liquidcrystal cell is used, there is no need to form the black matrix layer413.

Referring to FIG. 9, the operation of displaying an image in reflectiveand transmissive modes according to the present embodiment is describedbelow.

In the reflective displaying mode, ambient light incident from the upperside in FIG. 9 onto the liquid crystal device passes through thepolarizer 405, the retardation plate 406, and the liquid crystal layer403. The light further passes through the color filter 414 is thenreflected by the reflective films 411. The reflected light is output tothe outside via the polarizer 405. In this reflective displaying mode,the image brightness can be controlled by the voltage applied across theliquid crystal layer 403 into a bright, dark, or intermediate state.

In the case where an image is displayed in the transmissive displayingmode, light emitted from the backlight is converted by the polarizer 407and the retardation plate 408 into light with predetermined polarizationand introduced into the liquid crystal layer 403 via spaces betweenadjacent reflective films 411. After that, the light passes through thecolor filter 414, the liquid crystal layer 403, and the retardationplate 406. In this transmissive displaying mode, the light transmissionis controlled according to the voltage applied across the liquid crystallayer 403 into a state where the light passes through the polarizer 405(bright state) or a state where the light is absorbed by the polarizer405 (dark state) or otherwise into an intermediate state (withintermediate brightness).

By employing the structure described above with reference to the presentembodiment, it is possible to realize a color liquid crystal devicecapable of switching the displaying mode between the reflective andtransmissive modes in any of which an image can be displayed withoutproducing double images or dull images.

In the present embodiment, the reflective films 411 are formed of ametal layer chiefly containing Al. The surface of the reflective films411 are covered with the protective film 412. Furthermore, the colorfilter 414, the protective film 415, and the transparent electrodes 416are formed on the protective film 412. Therefore, the Al metal layer isprevented from coming into direct contact with the developing solutionsused to form the ITO film and the color filter and thus the Al metallayer is prevented from being dissolved into the developing solutions.Furthermore, the Al metal layer can be handled without damaging it. Forexample, a 25 nm thick Al metal layer added with 1.0 wt % Nd has areflectance of 80% and a transmittance of 10%, and thus it provides goodcharacteristics when used to form the reflective films 411.

Furthermore, the reflective films 411 having an uneven surface canreflect light over a wide range of angles, and thus it is possible toachieve a liquid crystal device having a wide viewing angle.

In the present embodiment, instead of forming the protective film overthe reflective films, an insulating film may be formed on the reflectivefilms by performing thermal oxidation or anodization as in the secondembodiment or coating an organic material on the reflective films.

In the transflective liquid crystal device according to theabove-described embodiments, light emitted from the backlight istransmitted via the spaces between adjacent reflective films. Instead ofor in addition to such a structure, small openings or slits may beformed in the reflective film(s) itself (themselves) so that lightemitted from the backlight is introduced into the liquid crystal layervia the openings. In this case, for each pixel, one or more openings areformed into the shape of a square, rectangle, slit, circle, or ellipseat regular or irregular intervals. Preferably, the openings are formedsuch that its total area becomes approximately equal to 10% of the totalarea of the reflective films. Such openings may be easily formed by aphotolithography process including a photoresist coating step, exposurestep developing step, and resist removing step, developing step, andresist removing step. The openings may be formed at the same time as thereflective films are formed. This allows the openings to be producedwithout needing additional processing steps. Whatever shape the openingsare formed into, it is desirable that the diameter of each opening bewithin the range from 0.01 μm and 20 μm, and that the total area of theopenings relative to the total area of the reflective films be withinthe range from 5% to 30% .

Seventh Embodiment

A seventh embodiment of a liquid crystal device according to the presentinvention is described below with reference to FIG. 11. FIG. 11 is across-sectional view illustrating in an enlarged fashion a TFT drivingdevice and other elements such as a pixel electrode according to thisseventh embodiment of the invention. The structure disclosed here inthis seventh embodiment in which TFT driving devices are formed on asubstrate and connected to transparent electrodes formed on the TFTdriving devices via an insulating film may also be applied to the otherembodiments of the present invention.

In the reflective or transflective liquid crystal device according tothe eight embodiment, as shown in FIG. 11, an interlayer insulating film721 is formed on a transparent substrate 702, and a TFT is formed on theinterlayer insulating film 721 wherein the TFT includes a gate electrode722, a gate, insulating film 723, an i-Si layer 724, an n⁺-Si layer 725,a source electrode 726, and a drain electrode 727. An interlayerinsulating film 731 is formed over the TFT, and a reflective film 728 isformed of aluminum on the interlayer insulating film 731. An insulatingfilm 729 is formed on the reflective film 728 by anodizing thereflective film 728. A transparent electrode 730 (pixel electrode) isformed of ITO over the insulating film 729 and connected to the drainelectrode 727 via a contact hole.

In this seventh embodiment, because electric power is supplied to eachtransparent electrode (pixel electrode) 730 via a corresponding TFT asdescribed above, cross-talk between different transparent electrodes 730is suppressed. This makes it possible to display an image with higherquality. When the TFT is formed using polysilicon, the TFT may be formedin any structure selected from the LDD structure, the offset structure,and the self-aligned structure. The number of gates of the TFT is notlimited to one, but the TFT may include two or more gates.

Eighth Embodiment

An eighth embodiment of a liquid crystal device according to the presentinvention is described below with reference to FIG. 12. FIG. 12 is across-sectional view illustrating in an enlarged fashion a TFD drivingdevice and other elements such as a pixel electrode according to aneighth embodiment of the invention. The structure disclosed here in thiseighth embodiment in which TFD driving elements are formed on asubstrate and connected to transparent electrodes formed on the TFTdriving elements via an insulating film may also be applied to the otherembodiments of the present invention.

In the reflective or transflective liquid crystal device according tothe eighth embodiment, as shown in FIG. 12, an interlayer insulatingfilm 821 is formed on a substrate 802, and a first conductive layer 841is formed of tantalum on the interlayer insulating film 821. Aninsulating layer 842 is formed on the first conductive layer 842 byanodizing tantalum. A second conductive layer 842 is formed of chromiumon the insulating layer 842. Furthermore, a reflective film 844 isformed of aluminum on the interlayer insulating film 821, and aninsulating film 845 is formed on the reflective film 844 by anodizingthe evaporated reflective film 844. A transparent electrode (pixelelectrode) 846 is formed on the insulating film 845 and connected to thesecond conductive layer 843.

In this eight embodiment, because electric power is supplied to eachtransparent electrode (pixel electrode) 846 via a corresponding TFD asdescribed above, cross-talk between different transparent electrodes 846is suppressed. This makes it possible to display an image with higherquality. Instead of the TFD shown in the figure, ZnO (zinc oxide)varistor, MSI (metal semi-insulator) driving device, or a two-terminalnon-linear device having two-way diode characteristics such as a RD(ring diode) may also be employed.

In this eighth embodiment, the TFD may be disposed on the side, fromwhich ambient light is input, of the transparent substrate andstripe-shaped reflective films and transparent electrodes may be formedon the side, from which light emitted from the backlight is input, ofthe transparent substrate to obtain similar effects.

Referring now to FIG. 13, the colored layers of the color filter 213,313, or 414 used in the first to eighth embodiments are described below.FIG. 13 is graph illustrating the transmittance of the respectivecolored layers of the color filter 213 or the like. In any embodiment,when an image is displayed in the reflective displaying mode, incidentlight passes through one of colored layers of the color filter 213 orthe like and further passes through the liquid crystal layer. The lightis then reflected by the reflective films and passes again through oneof the colored layers. After that, the light is output to the outside.Thus, as opposed to usual reflective liquid crystal devices, lightpasses twice through the color filter 213 or the like. Therefore, if ausual type color filter is employed, the brightness and the contrast ofan image displayed become low. In each embodiment, to avoid such aproblem, the color filter 213 or the like is formed to have lightlycolored layers of R, G, and B each having minimum transmittance 61 inthe visible region which sets to 25 to 50% , as shown in FIG. 13. Thelightly colored layers may be obtained by reducing the thickness of eachcolored layer or by reducing the concentration of pigments or dyescontained in the respective colored layers. The employment of thelightly colored layers makes it possible to display an image in thereflective displaying mode without causing a reduction in thebrightness.

The employment of the color filter 213 having lightly colored layerscauses the displayed image to have lighter colors in the transmissivedisplaying mode because light passes only once through the color filter213 in the transmissive displaying mode. This is desirable in that abrighter image can be obtained, if the fact that in any embodiment alarge amount of light emitted from the backlight is blocked by thereflective films is considered.

Ninth Embodiment

A ninth embodiment of the present invention is described below withreference to FIG. 14. This ninth embodiment is concerned with electronicapparatuses each including a liquid crystal device according one of thefirst to eighth embodiments described above. That is, the ninthembodiment is concerned with various types of electronic apparatus inwhich a reflective or transflective liquid crystal device according toone of the first to eighth embodiments is advantageously used as adisplay unit of portable devices which need to operate with low electricpower in various environments. FIG. 14 illustrates three examples ofelectronic apparatuses according to the present invention.

FIG. 14(a) illustrates a portable telephone including a display unit 72disposed on the upper side of the front panel of a main body 71.Portable telephones are used indoors and outdoors under variousconditions. In particular, portable telephones are often used in cars.When a portable telephone is used in a car at nighttime, the inside ofthe car is very dark. Therefore, for use as the display unit in theportable telephone, it is desirable to employ a transflective liquidcrystal device capable of displaying an image in the reflectivedisplaying mode with low power consumption in most cases and alsocapable of displaying an image in the transmissive displaying mode usingauxiliary light as required. If the liquid crystal device according toone of the first to eighth embodiments is employed as the display unit72 of the portable telephone, the display unit 72 of the portabletelephone can display an image with a higher brightness and a highercontrast in both the reflective and transmissive displaying mode thancan be obtained by a conventional portable telephone.

FIG. 14(b) illustrates a watch including a display unit 74 disposed inthe center of the main body 73. An important item required for watchesis a high-class appearance. If a liquid crystal according to one of thefirst to eighth embodiments of the present invention is employed as thedisplay unit 74 of a watch, not only a high brightness and a highcontrast are achieved but also coloring is minimized because variationsin characteristics depending on the wavelength of light are small. Thus,it is possible to realize a watch with a color display unit having anextremely high-class appearance compared to conventional watches.

FIG. 14(c) illustrates a portable information device including a displayunit 76 disposed on the upper side of the main body 75 and an input unit77 disposed on the bottom side. In most cases, a touch key is providedon the front surface of the display unit 76. In general, the touch keyis difficult to see because of large surface reflection. To reduce sucha difficulty, a transmissive liquid crystal device is employed in manycases as the display unit even in portable type devices. However, thetransmissive liquid crystal device consumes large electric power becausethe backlight is always used. Therefore, the battery life is short. Alsoin this case, a liquid crystal device according to one of the first toeighth embodiments can be advantageously employed as the display unit 76of the portable information device thereby ensuring that a bright andclear image is displayed in any displaying mode, reflective,transflective, or transmissive mode.

The liquid crystal device according to the present invention is notlimited to those described above with reference to particularembodiments. Various modifications are possible without departing thespirit and the scope defined in the claims or read from the description.It should be understood that any liquid crystal device with such amodification also falls within the scope of the present invention.

Industrial Applicability

The liquid crystal device according to the present invention can beemployed to realize various types of display devices capable ofdisplaying an image with a high brightness and a high contrast. Theliquid crystal device according to the present invention can also beemployed as a display unit in various electronic apparatuses. Theelectronic apparatus including the liquid crystal device according tothe present invention can be used as a liquid crystal television set, avideo tape recorder with a view-finder or a minitor display, a carnavigation system, an electronical personal organizer, an electroniccalculator, a word processor, an engineering workstation, a portabletelephone, a vidio telephone, a POS terminal, a touch panel, etc.

1. A liquid crystal device comprising: first and second substrates, a liquid crystal layer disposed between said first and second substrates; a plurality of transparent electrodes which are formed above a surface of said second substrate on the side of said liquid crystal layer, said plurality of transparent electrodes being spaced from each other in a horizontal direction when seen in a direction perpendicular to said second substrate; and a plurality of reflective films formed between said plurality of transparent electrodes and said second substrate, in areas opposing respective ones of said plurality of transparent electrodes, said plurality of transparent electrodes being formed directly on said reflective films, wherein said transparent electrodes are also formed in at least some part of a space between the plurality of reflective films.
 2. The liquid crystal device according to claim 1, wherein said reflective films are arranged in correspondence with respective ones of said plurality of transparent electrodes.
 3. The liquid crystal device according to claim 1, further comprising a color filter formed on at least one of said first and second substrates, said color filter including colored areas opposing respective ones of said transparent electrodes, wherein said color filter includes no light shielding area in an area opposing at least some part of a space between said transparent electrodes.
 4. The liquid crystal device according to claim 1, wherein said reflective films further comprise insular reflectors further comprise insular.
 5. A liquid crystal device comprising: a first substrate; a second substrate disposed opposite to said first substrate; a liquid crystal layer disposed between said first and second substrates; a plurality of reflectors formed on said second substrate on the side of said liquid crystal layer, said reflectors being spaced apart from each other; and a plurality of transparent electrodes formed on respective ones of said reflectors, wherein said transparent electrodes are also formed in at least some part of a space between the plurality of reflectors.
 6. The liquid crystal device of claim 5 further comprising a color filter on respective ones of said plurality of transparent electrodes.
 7. The liquid crystal devices of claim 6, wherein said color filter are not disposed between said transparent electrodes.
 8. The liquid crystal devices of claim 6, wherein said color filters are also formed in an area opposing at least some part of a space between the plurality of reflectors.
 9. The liquid crystal devices of claim 5 further comprising a plurality of switching elements, each of said switching elements being connected with respective ones of said transparent electrodes.
 10. The liquid crystal device according to claim 5, wherein said reflectors further comprise insular.
 11. A liquid crystal device comprising: a first substrate; a second substrate disposed opposite to said first substrate; a liquid crystal layer disposed between said first and second substrates; a plurality of transflector formed on said second substrate on the side of said liquid crystal layer, said transflectors being spaced from each other; a plurality of transparent electrodes formed on respective ones of said transflectors; and a backlight positioned on an opposite side of said second substrate with respect to said liquid crystal layer, wherein said transparent electrodes are also formed in at least some part of a space between the plurality of transflectors.
 12. The liquid crystal device of claim 11 further comprising: a polarizer disposed between said second substrate and said backlight; and a retardation film disposed between said second substrate and said polarizer.
 13. The liquid crystal device of claim 11, further comprising a color filter disposed on respective ones of said transparent electrodes.
 14. The crystal devices of claim 13, wherein said color filters are also formed in an area opposing at least some part of a space between the plurality of transflectors.
 15. The liquid crystal device of claim 11 further comprising a plurality of switching elements, each of said switching elements being connected with respective ones of said transparent electrodes.
 16. The liquid crystal device of claim 11, wherein said transflectors further comprise a reflective film having an opening.
 17. The liquid crystal device according to claim 11, wherein said transflectors further comprise insular.
 18. An electronic device comprising: a main body; and a display unit including a liquid crystal device, said liquid crystal device including: a first substrate; a second substrate disposed opposite to said first substrate; a liquid crystal layer disposed between said first and second substrates; a plurality of reflectors formed on said second substrate on the side of said liquid crystal layer, said reflectors being spaced from each other; and a plurality of transparent electrodes formed on said plurality of reflectors, wherein said transparent electrodes are also formed in at least some part of a space between the plurality of reflectors.
 19. An electronic device, comprising: a main body; and display unit including a liquid crystal device, said liquid crystal device including: a first substrate; a second substrate disposed opposite to said first substrate; a liquid crystal layer disposed between said first and second substrates; a plurality of transflectors formed on said second substrates on the side of said liquid crystal layer, said transflectors being spaced from each other; a plurality of transparent electrodes formed on said transflectors; and a backlight positioned on an opposite side of said second substrate with respect to said liquid crystal layer, wherein said transparent electrodes are also formed in an area opposing at least some part of a space between the plurality of transflectors. 